API Security Best Practices Review the request boundary from caller identity through authorization, validated input, storage and observable response. Preserve the application's actual identity provider and data model rather than introducing a second authentication system. When to Use Use when adding a protected endpoint, reviewing object access, replacing permissive request parsing, or investigating an API abuse path. For a concrete defect, start with the failing route and its callers; do not deploy unrelated security infrastructure. Inputs and prerequisites Record the routes, caller/tenant m…